Greens

Topic summary contributed by volunteer(s): Randy

People may have gained health benefits from wild greens as long as 200,000 years ago. Today, greens are considered one of the healthiest vegetables, and they’re inexpensive. Organic greens may be healthier than non-organic greens due to their defensive response to getting bitten by bugs. 

The calcium in dark green leafy vegetables is more effectively absorbed by the body than that found in cow’s milk. Potassium from greens may be anti-inflammatory and may prevent strokes and heart disease.  Greens can also provide iron and zinc, antioxidants, and magnesium, a nutrient that may lower the risk of a range of health concerns including diabetes, heart disease, and sudden cardiac death.  Green leafy vegetables are the best source of plant-based nitrates. Nitrates from a plant-based diet are not considered harmful. In fact, nitric oxide formed from plant-based nitrate may play a role in the prevention of heart disease and high blood pressure. Eating whole plant foods is likely better for your health than taking supplements.  For example, folate, which can reduce the risk of depression, in greens appears preferable to folic acid supplements. Many nutrients found in greens are fat soluble, which means including some healthy whole food fats like nuts or seeds, in a meal can help you better absorb the phytonutrients.  Plant-based diets, including greens, tend to be alkaline-forming, which may help protect muscle mass and reduce the risk of gout and kidney stones. High consumption in particular of green leafy and cruciferous vegetables may be linked to lower rates of cognitive decline. Greens can be an important part of a plant-based diet that could reduce risk for cardiac disease  and heart attack. Some nutrients are destroyed by cooking, but some nutrients become more absorbable. So, a mix of cooked and raw vegetables, including greens, may be best. Smoothies may also be a great source to get all of the nutrients greens have to offer. Although make sure to drink whole food smoothies (not made from juice), and it may be better to use a straw to prevent enamel erosion.

Consuming at least one serving a month of greens appears to reduce the risk of glaucoma by 69%. Lutein and zeaxanthin, nutrients found greens, also appear to be protective against cataracts and macular degeneration. Greens consumption is also associated with increased physical attractiveness, reduced facial wrinkling, improved dental health, better immune system, and may reduce free radical DNA damage.

Two or more daily servings of greens may help clear the human papilloma virus, which can cause cancer. Eating green leafy vegetables may also reduce risk for breast cancer, kidney cancer, and lymphoma, and overall cancer risk. Adding mustard powder o cooked greens can boost sulforaphane levels to help protect against cancer.

Overall, most people in the U.S. fall short in meeting guidelines set by the USDA. For example, nine out of ten Americans could not meet the recommended minimum for vegetables (nine servings a day), including dark green vegetables.

Note: If you’re eating cups a day (as everyone should!) of dark green leafy vegetables Dr. Greger recommends sticking to low-oxalate greens (i.e. basically any greens other than spinach, swiss chard, and beet greens).

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